Such a heat exchanger is assembled without any welding or soldering, sealing of the tubes to the tube plate being obtained by means of an elastomeric gasket. When such a heat exchanger is handled either before or during its assembly into a vehicle, or even after it has been fitted into the vehicle, it does happen in some cases that relative movements of the tube bundle, in particular in a pivoting mode or due to torsion, take place with respect to the assembly consisting of the tube plate and the header. Such relative movement may be caused by pressure and mechanical stresses transmitted to the headers through the mounting points of the heat exchanger. This pivoting or torsion effect is particularly critical when the tube bundle has only a single range of tubes.
In order to overcome this disadvantage, it is known to connect the two headers of a heat exchanger together by means of cross members which impart some rigidity to the assembly. However, a disadvantage of this arrangement is that it necessitates additional components, requires a header of special design, and calls for a specialized machine for seaming the cross members in place.
Other solutions have also been proposed for providing rigid connection between a bundle of tubes and an assembly consisting of a tube plate and a header. Thus for example, French patent No. 84 02964, published under the number 2 560 368, describes a heat exchanger which includes retaining means that cooperate with fins or the like carried by the tubes in the bundle. The purpose of these retaining plates is to resist any relative displacement, in particular in a pivoting or torsional mode, of the tube bundle with respect to the assembly consisting of the tube plate and the header. In this known heat exchanger, however, these retaining means consist of lugs which are formed by molding with the header, which makes it necessary again to provide specially designed headers.